The famous Arecibo Observatory in Puerto Rico may be forced to close, it has been revealed, due to a lack of funding. Earlier this month, the US National Science Foundation (NSF) said they were attempting to find new partners to keep the radio telescope going, but time is running out.

It costs about $12 million a year to run the observatory, which at 305 meters (1,000 feet) across was the largest radio telescope in the world until China’s Five Hundred Meter Aperture Spherical Telescope (FAST) came online last year. About $4 million of this comes from NASA, with another $8 million from the NSF.

But the NSF is seeking to fund new ventures, and federal budget cuts mean that Arecibo is one project on the chopping block. The NSF is accepting proposals from interested parties to take over the running costs of Arecibo, with a deadline in late April. If no suitable proposal is put forward, Arecibo’s days as a hotbed of astronomy may be over.

“All the other options would require the Arecibo to halt its current work and either become a museum or be mothballed or dismantled,” Nicholas White, senior vice-president of the Universities Space Research Association (USRA), which helps to manage Arecibo for the NSF, told the Observer. “From that perspective, the situation looks grim.”

Since it was opened in 1963, Arecibo has made numerous significant discoveries including refining the rotation rate of Mercury from 88 days to 59 days, and finding the first confirmed planet outside the Solar System – PSR B1257+12 B, which orbits a pulsar.

^{Arecibo transmitted the Arecibo Message in 1974 to a globular star cluster, in the hope of making contact with intelligent life. Jarmo Kivekas}

It was built to make use of a depression in the ground left by a sinkhole in Puerto Rico, meaning the dish could be much larger than other telescopes, which require a metal framework to support their dishes. About 150 meters (490 feet) above the dish is a large 900-ton (820 metric tonnes) receiver, which can move to observe almost a quarter of the sky above.

Aside from its astronomy credentials, Arecibo also played a starring role in two movies – 1995's Goldeneye, which saw James Bond face off with villain Alec Trevelyan on the suspended platform, and the 1997 science-fiction movie Contact.

Now, though, the NSF wants to move funds to other projects. One of these is the Large Synoptic Survey Telescope (LSST), a relatively large reflecting telescope under construction in Chile, due to open in 2019, that will survey the entire sky.

Arecibo is not the only telescope up for the chop; others, including the Green Bank radio telescope in West Virginia, are also in danger. But Arecibo is perhaps the most iconic – and Scientific American notes that a draft statement from the NSF “even details which explosive would be needed to dismantle the 305-metre-wide dish.”